Today I Learned - Rocky Kev

TIL Destructuring a array

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TAGS: javascript destructuring

Another post about destructuring! I love destructuring and I keep forgetting how to use it effectively.


const heroes = [{
  firstName: "Clark",
  lastName: "Kent",
  heroName: "Superman",
  species: "Kryptonian",
  age: 34
},
{
  firstName: "Diane",
  lastName: "Prince",
  heroName: "Wonder Woman",
  species: "Amazonian",
  age: 800
},
{
  firstName: "Bruce",
  lastName: "Wayne",
  heroName: "Batman",
  species: "Human",
  age: 30
}];

How to get:

// I only want Clark
const [{firstName},] = heroes; // Clark

// I only want Batman
const [, , {heroName} ] = heroes; // Batman

// I want everyone's hero names
//  ['Superman', 'Wonder Woman', 'Batman']
const heroNames = heroes.map(hero => hero.heroName)

// I want all the details about Bruce Wayne
const theBatmanObject =  heroes.find(hero => hero.heroName === 'Batman'); // { ... }
const theBatmanArray =  heroes.filter(hero => hero.heroName === 'Batman'); // [{ ... }]

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